Ancient Mesoamericans Kept and Bred Dangerous Predators 1000 Years Earlier Than We Thought

When you see a lion, a tiger or a bear in a zoo, it’s easy to forget that people haven’t always so easily controlled big carnivores and other dangerous animals. For a long time, people were simply prey, but almost every civilization around the world has taken the upper hand over predators at some point, exploiting them for food, entertainment, and ritual uses. In ancient Egypt, crocodiles were sacrificed and mummified. On the other side of the Mediterranean, the Romans used various carnivores in gladiatorial battles and horrific "halftime" displays.

In the New World, that point has usually been fixed sometime in the 16th century, when the Aztec ruler Montezuma established a zoo in the city of Tenochtitlan. Multiple buildings and hundreds of workers were dedicated to importing, breeding, and caring for animals like wolves, jaguars, foxes, rattlesnakes, and birds of prey that served as offerings to the gods at the city’s Great Temple.

Now, a recent study published in PLOS One suggests that long before the rise of the Aztec Empire, Mesoamericans were capturing and breeding some of the region’s most intimidating predators and using them as both sacrifices and displays of power. Archaeological findings from the city of Teotihuacan push the earliest example of people keeping captive carnivores in the New World back by 1000 years.

Located 30 miles northeast of modern day Mexico City, Teotihuacan was one of Mesoamerica’s largest pre-colonial cities, home to perhaps 125,000–200,000 people. It was an important political and religious center, and the site of three large temples: the Temple of Quezalcoatl, the Pyramid of the Sun, and the Pyramid of the Moon.

During excavations of the latter two, researchers found caches of ritual offerings throughout the buildings. Among them were carved obsidian, shell and stone crafts, human sacrifices, and the remains of nearly 200 carnivorous animals, including golden eagles, pumas, jaguars, wolves, and rattlesnakes.

To learn more about the relationship between these beasts and the people who apparently kept, cared for, and ultimately killed them, a team of anthropologists led by Nawa Sugiyama of the National Museum of Natural History looked for clues about the lives of the animals in their bones. They examined 66 complete skeletons and more than 100 loose bones and found evidence that many of the animals lived in captivity. Several of the eagle skeletons, for example, all showed the same signs of stress on the inner parts of the legs, likely from being tethered to perches. Many eagle, puma, and wolf skeletons displayed fractures and bone diseases that suggested infection and injury from being kept in confined spaces and roughly handled. Some of the skeletons also had bones from other animals inside their rib cages. These turned out to belong to rabbits and hares, and many were burnt, suggesting they’d been cooked and fed to the carnivores.

Rabbits weren’t the only thing the animals were eating. A chemical analysis of the bones revealed high levels of carbon isotopes that reflect a diet heavy in plants like maize, which these animals normally wouldn’t consume in the wild. More than half of one eagle’s diet appears to have been made up of maize and other plants.

The team also found nitrogen levels in some of the bones that reveal a grisly detail of the animals’ lives and the rituals that took place at Teotihuacan. A few of the pumas' skeletons had “exceptionally high” levels of a certain nitrogen isotope that points to the cats eating not only plants and plant-eating herbivores, but omnivores higher up on the food chain.

These pumas, the researchers think, may have been fed meat from dogs or even humans. These meats might not have just been supplementary protein, but part of a ritual. In Teotihuacan, the researchers note there are numerous depictions of carnivores eating human hearts and even taking part in human sacrifices, dressed in military clothing and holding knives. There’s similar art at other Mesoamerican sites, and some Spanish conquistadors described the carnivores housed in Montezuma’s zoo being fed the remains of humans used in sacrificial rites.

Keeping dangerous predators as both sacrifices and as means to sacrifice humans—and being the first to do so in Mesoamerica—would have been an incredible display of power and “premier expression of state ideology and militarism” for the rulers of Teotihuacan, the researchers say. But their finds make it clear that pioneering a shift in human-predator dynamics wasn’t easy on the animals or the people.

“Specimens like the eagle attest to the hardships in learning to manipulate highly specialized carnivores,” the team writes. “Caring for and manipulating the region’s most dangerous apex predators sometimes required the use of brute force as evidenced by an unnaturally high frequency of healed fractures, violent injuries, bone deformity and disease.”

Dumbo octopuses are named for the elephant-ear-like fins they use to navigate the deep sea, but until recently, when and how they developed those floppy appendages were a mystery. Now, for the first time, researchers have caught a newborn Dumbo octopus on tape. As reported in the journal Current Biology, they discovered that the creatures are equipped with the fins from the moment they hatch.

Study co-author Tim Shank, a researcher at the Woods Hole Oceanographic Institution in Massachusetts, spotted the octopus in 2005. During a research expedition in the North Atlantic, one of the remotely operated vehicles he was working with collected several coral branches with something strange attached to them. It looked like a bunch of sandy-colored golf balls at first, but then he realized it was an egg sac.

He and his fellow researchers eventually classified the hatchling that emerged as a member of the genus Grimpoteuthis. In other words, it was a Dumbo octopus, though they couldn't determine the exact species. But you wouldn't need a biology degree to spot its resemblance to Disney's famous elephant, as you can see in the video below.

The octopus hatched with a set of functional fins that allowed it to swim around and hunt right away, and an MRI scan revealed fully-developed internal organs and a complex nervous system. As the researchers wrote in their study, Dumbo octopuses enter the world as "competent juveniles" ready to jump straight into adult life.

Grimpoteuthis spends its life in the deep ocean, which makes it difficult to study. Scientists hope the newly-reported findings will make it easier to identify Grimpoteuthis eggs and hatchlings for future research.

Ursus arctos horribilis is better known by the more casual term of grizzly bear. These massive, brown-haired predators have a reputation as one of nature’s most formidable killing machines. Standing up to 8 feet tall and weighing 800 pounds, these fierce mammals have captivated—and frightened—humans for centuries. Keep your distance and read up on these facts about their love for munching moths, eating smaller bears, and being polar-curious.

1. THEY’RE ACTUALLY PRETTY LIGHT EATERS.

Grizzlies—more accurately, North American brown bears—are strong enough to make a meal out of whatever they like, including moose, elk, and bison. Despite their reputation for having carnivorous appetites, their diet also consists of nuts, berries, fruits, and leaves. They’ll even eat mice. The gluttony doesn’t kick in until they begin to exhibit hyperphagia, preparing for winter hibernation by chomping down enough food to gain up to three pounds a day.

2. THEY USE “CPR” TO GET AT YOUR FOOD.

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More than 700 grizzlies live in or near Yellowstone National Park, which forces officials to constantly monitor how park visitors and the bears can peacefully co-exist. Because bears rummaging in food containers can lead to unwanted encounters, the park’s Grizzly & Wolf Discovery Center tests trash cans and coolers to see if they’re bear-resistant. (Nothing is truly bear-proof.) Often, a bear will use “CPR,” or jumping on a canister with its front legs, in order to make the lid pop off. Containers that can last at least 60 minutes before being opened can be advertised by their manufacturers as being appropriate for bear-inhabited environments.

3. THEY CAN CLIMB TREES.

It's a myth that grizzlies can't climb trees. Though their weight and long claws make climbing difficult [PDF], and they need support from evenly-spaced branches, grizzlies can travel vertically if they choose to.

4. THEY’LL EAT OTHER BEARS.

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In addition to being omnivorous, grizzlies can also be classified as cannibals. They’ve been spotted eating the carcasses of black bears in Canada. Calling it a “bear-eat-bear world,” officials at Banff National Park in Alberta said the grizzlies are “opportunistic” and more than willing to devour black bears—sometimes just one-fifth their size—if the occasion calls for it. And it’s not just black bears: One study on bear eating habits published in 2017 recorded a 10-year-old male eating a 6-year-old female brown bear.

5. THEY LOVE MOTHS.

Although grizzlies enjoy eating many insects, moths are at the top of the menu. Researchers have observed that bears are willing to climb to alpine heights at Montana’s Glacier National Park in order to feast on the flying appetizers. Grizzlies will turn over rocks and spend up to 14 hours in a day devouring in excess of 40,000 moths.

6. A PAIR OF THEM ONCE LIVED ON WHITE HOUSE GROUNDS.

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In what would be considered an ill-advised decision, explorer Zebulon Pike decided to gift his friend President Thomas Jefferson with two grizzly cubs in 1807. Jefferson reluctantly accepted them and kept them in a cage near the north entrance to the White House, and later re-gifted the cubs to museum operator Charles Willson Peale. Sadly, one of them got shot after getting too aggressive with Peale’s family.

7. THEY CAN RUN FASTER THAN USAIN BOLT.

The bears we see in fiction or lazing about in the wild tend to look cumbersome and slow, as most anything weighing nearly a half-ton would. But in a land race, even Olympic champions would be on the losing end. Grizzlies can reportedly run 35 mph, and sustain speeds of up to 28 mph for two miles, faster than Usain Bolt’s 27.78 miles per hour stride (which he can only sustain for a few seconds).

8. THEY MATE WITH POLAR BEARS.

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In parts of Alaska and Canada where grizzlies and polar bears converge, there are sometimes rare sightings of what observers call “grolar bears” or “pizzlies.” With large heads and light-colored fur, they’re a hybrid superbear birthed from some interspecies mating. Typically, it’s male grizzlies who roam into those territories, finding female polar bears to cozy up with. Researchers believe climate change is one reason the two are getting together.

9. THEY KNOW HOW TO COVER THEIR TRACKS.

When it comes to intellect, grizzlies may not get all the same publicity that birds and whales do, but they’re still pretty clever. The bears can remember hotspots for food even if it’s been 10 years since they last visited the area; some have been observed covering tracks or obscuring themselves with rocks and trees to avoid detection by hunters.

10. THEY’RE NOT OUT OF THE WOODS YET.

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For 42 years, grizzlies at Yellowstone occupied the endangered species list. That ended in 2017, when the U.S. Fish and Wildlife Service declared that a rise in numbers—from 150 in the 1970s to more than 700 today—meant that conservation efforts had been successful. But overall, the grizzly population is still struggling: Fewer than 2000 remain in the lower 48 states, down from 50,000 two centuries ago.